Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hanh lai » hanh lam, hanh tai, thanh lap
hieu va » lieu va, hieu qua
lai cua » dai cua, hai cua, lai chau
so sach » so sanh, bo sach, co sach
tang ma » mang may, tang van
hieu ve » hieu van
y tang » ky tang, 6 tang, 7 tang
tuc va » thuc va, truc va, duc va
ma hoi » mai hoi, xa hoi, ma hoa

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: so sach y tang ma hoi. ((hieu ve) OR (hieu va)) cam ((tuc va) or (tuc xa)) hanh lai cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach y tang ma hoi. ((hieu ve) OR (hieu va)) cam ((tuc va) OR (tuc xa)) hanh lai cua triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach y tang ma hoi. ((hieu ve) OR (hieu va)) cam ((tuc va) or (tuc xa)) hanh lai cua triet*".